Millie Davis is a Canadian actress who is best known for her roles as Ms. O in the PBS Kids series Odd Squad, Summer in the film Wonder, and Gemma Hendrix in the series Orphan Black. She was nominated for a Best Actress award as Ms. O in Odd Squad: The Movie at the 5th Canadian Screen Awards and has been co-nominated with the Odd Squad cast for four additional awards, including winning the award for "Best Young Ensemble in a TV Series" at the 2015 Joey Awards.

Davis was born in Toronto, Ontario, to Megan and Wayne Davis. Her older brother, Drew Davis, is also an actor, who has appeared in Orphan Black, among other roles. Her parents run the Charactors Theatre Troupe in Thornhill, Ontario.

Davis began her career in acting at the age of 6 months when she first appeared in a commercial with her father and she began TV roles beginning shortly before she turned 4.

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